Aluminization Details

Leave a Comment The MMT primary mirror was successfully recoated on September 2, with the coating being uniform across the entire mirror. The measured reflectivity in the blue (at 400nm) is 91.6%, the best achieved at the MMT to date. A minor imperfection is a thin coating along a small area of the south edge (around 6:30) where the glass was shadowed by aluminum foil used to protect the mylar vacuum barrier. Take a look at a photo (you can zoom in), the reflectance plot, and a video of the shot!